The lion wraps its arms around Richardson and rubs its head against his in a surprising scene of affection that's been viewed nearly 650,000 times on YouTube. He shoves the huge cat aside as a second approaches, its furry mane rustling as it jogs forward and smothers Richardson in a second lion hug.
Richardson calls to him like he's a puppy dog, referring to him as "lover boy."
The three unlikely friends topple into the grass, cuddling as Richardson pets their fur. They look so much like overgrown domestic cats it seems easy to forget these beasts can run up to 81 kilometres an hour for short distances and they have teeth designed for munching on zebras.
Richardson's website describes him as a "self-taught animal behaviourist" who breaks the established rules about how to relate to wild animals, choosing to build trust rather than tame them aggressively.
Past footage has shown lions that seem smitten with humans, such as the famous lion hug in the documentary Christian The Lion.
A video of a dog cleaning a lion's teeth went viral earlier this year.
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